Newsletter

Volume 9

Welcome to the ninth edition of ArchNews, Archetype Joint’s independent newsletter bringing you the latest in fastening and joining technology. If you have any comments or suggestions for a coming edition of ArchNews, please contact me at 248 377-1147 or darcher@archetypejoint.com .

Dave Archer
President
Archetype Joint, LLC

Wave Threads – Looking for your help

Earlier this year I was contacted by an inventor inquiring whether I might be interested in finding applications for a proprietary thread form he had developed. It’s claimed benefit was high-strength, self-locking and self-sealing connections. Find out more in this article.

Archetype Joint in the News

Since the last edition of ArchNews was released, we’ve had five technical articles published in leading trade magazines. Read about it In The News.

Archetype Joint Enhances Test Capabilities

While most of our customers have torque-tension testing performed to understand bolt tension, others are also interested in actual elongation measurement. Load vs. elongation testing allows more accurate estimates of joint behavior over a wide range of conditions, not just those tested. The bolt extensometer shown in Figure 1 allows measurement of overall bolt elongation for bolts to 6” (with provisions for range extension). By taking measurements in-joint, joint stiffness can also be calculated as is required for calculating the effect of external loading. Perhaps the most common use of the bolt extensometer is in determining proof load; the greatest load that does not result in permanent deformation. The bolt extensometer is an extension of our test capability using the more traditional knife edge extensometer, which can measure elongation within specific lengths of a test specimen.

Use of Washers and Flange Heads

It is likely that most common answer to the question “What is the main benefit of flat washers or flange head nuts and bolts?” would be that the increased bearing area they provide distributes the bolt load over a greater area thus decreasing the potential for compressive yield. While true, during testing we were able to get visual evidence of two important conditions that go against many people’s assumptions. Find out more in this article.

Drive Features – How Low Can You Go?

Here in metro Detroit, a popular subject for editorials and panel debate is why it seems the passion America once held for the automobile is in decline. Does the legislation and message coming out of Washington promote the development of appliances on wheels? Are manufacturers too risk-adverse and infested with a “bean-counting” mentality to ignite a passion dormant only through a lack of interesting product to awaken it? Find out about our test results in this article.